A team of researchers from around the world has successfully produced, stored, and retrieved quantum information for the first time, a crucial advancement in the field of quantum physics. Sharing quantum information is essential for developing networks for distributed computing and secure communication, which will be instrumental in solving complex problems such as optimizing financial risk and designing molecules.
One of the challenges in developing quantum networks is the loss of quantum information over long distances. To overcome this, researchers have proposed dividing the network into smaller segments and linking them with shared quantum states. This requires a quantum memory device to store and retrieve the information, which was achieved by the research team using regular optical fibers to transmit the data.
The researchers, from institutions such as Imperial College London and the universities of Stuttgart and Wurzburg in Germany, successfully interconnected the key components of quantum networking for the first time. This milestone opens up possibilities for long-distance connection between locations and quantum computers, which is essential for future quantum networks.
In traditional telecommunications, repeaters are used to read and re-amplify signals over long distances to ensure they reach their destination intact. However, classical repeaters cannot be used with quantum information as any attempt to read and copy it would destroy the information. Quantum networks overcome this barrier by sharing entangled photons, which are linked in a way that one cannot be understood without the other.
By creating a system where the devices producing and storing quantum information operate at the same wavelength, the research team was able to efficiently interconnect these components. The system utilized a quantum dot to produce non-entangled photons, which were then stored using a quantum memory system within a cloud of rubidium atoms.
While standalone quantum dots and memories have been developed previously, this achievement marks the first successful demonstration of interconnecting these devices at telecommunications wavelengths. The team plans to further improve the system by enhancing photon storage time and reducing its size, representing a significant advancement in the field of quantum networking.